There is a lot of incomprehensible in the history of this gun, from the moment of development, starting with the caliber and ending with what appeared in the end. But the main thing is the result, isn't it?
Where did the 85 mm caliber come from, it was not possible to establish at all. Sources are generally silent on this topic, as if just someone took it and decided to invent something like that. The only thing that could more or less serve as a starting point was the British 18-pound (83.8 mm or 3.3 ) QF cannon of the 1904 model, which was an enlarged version of the 13-pounder (76.2 mm) cannon and very very much like her in everything except size.
A number of such guns fell into the Red Army during the Civil War, and were also in service with the Baltic states.
Until 1938, there was no 85 mm caliber in Russian artillery at all. Occasionally he appeared in sketch projects, but it did not even come to contests. It seems that the phenomenon of this caliber really turned out to be accidental.
In 1937/1938, the designers of Plant No. 8 decided to use the good safety margins laid down in the project of the German gun "Rheinmetall", which we adopted under the name "76-mm anti-aircraft gun model 1931." and increase its caliber.
According to calculations, the limiting caliber that could be placed in the casing of a 76-mm cannon was 85 mm. The understanding of the need to adopt medium-caliber anti-aircraft artillery was justified, so 85-mm anti-aircraft guns were launched into mass production before the war.
But this, I repeat, is only speculation.
It is also very difficult to say why the Red Army was not satisfied with the new 76-mm anti-aircraft gun designed by Loginov, which was a revision of the 3-K cannon, which we have already written about.
The 76-mm anti-aircraft gun of the 1938 model of the year was just put into service when the 85-mm anti-aircraft gun of the 1939 model immediately replaced it.
The designer GD Dorokhin took the development of the same Loginov - a 76-mm anti-aircraft gun of the 1938 model as a basis. Dorokhin proposed to put a new 85-mm barrel on the platform of the 76-mm anti-aircraft gun, using also its bolt and semi-automatic.
The tests showed the need for further modifications caused by an increase in the caliber of the projectile, the weight of the powder charge and the weight of the installation itself. After increasing the supporting surface of the bolt wedge and the breech socket, as well as installing the muzzle brake, the gun was adopted by the Red Army under the name “85-mm anti-aircraft gun mod. 1939 g. or 52-K.
Many authors write that an important feature of the new anti-aircraft gun was its versatility: 52-K was suitable not only for fire on enemy aircraft, but was also successfully used as an anti-tank gun, firing at enemy armored vehicles with direct fire.
Considering that the 52-K received all the mechanisms from the 76 mm cannon, everything was equally true for its predecessor. However, the use of a more powerful projectile and powder charge provided more armor penetration compared to the 76-mm gun.
The 76-mm cannon fired high-explosive and armor-piercing shells. For the 85-mm gun, the 53-UBR-365K armor-piercing tracer sharp-headed caliber projectile and the 53-UBR-365P armor-piercing tracer sabot projectile were developed.
At a 76-mm gun, an armor-piercing caliber projectile with an initial speed of 816 m / s at a distance of 500 m pierced armor with a thickness of 78 mm, and at a distance of 1000 m - 68 mm. The direct shot range was 975 m.
The shell for the 85 mm cannon had better performance.
When firing at an angle of 60 °, a 9, 2-kg projectile penetrates armor about 100 mm thick at a distance of 100 m, 90 mm at a distance of 500 m, and 85 mm at a distance of 1000 m.
At a meeting angle of 96 ° at a distance of 100 m, armor penetration with a thickness of about 120 mm is ensured, at a distance of 500 m - 110 mm, at a distance of 1000 m - 100 mm.
The 85-mm armor-piercing tracer projectile weighing 4, 99 kg had an even greater armor-piercing ability.
The firing range of the 85mm cannon was also slightly longer than that of the 76mm cannon. In height: 10230 m, at a distance: 15650 m, for a 76-mm cannon, respectively, in height: 9250 m, at a distance: 14600 m.
The initial velocity of the projectile was approximately equal, in the region of 800 m / s.
In principle, it turns out that the appearance of the 85-mm cannon was justified. As well as some haste in the development is fully justified. The gun came out more powerful, immediately on a more transportable four-wheeled platform, and most importantly, it could successfully act as an anti-tank gun at the time of the appearance of heavy tanks from the Germans in 1942/43.
The creation of a new, four-wheeled platform ZU-8 made it possible to transport the anti-aircraft gun at speeds up to 50 km / h, instead of 35 km / h in its predecessors. The combat deployment time has also decreased (1 minute 20 seconds versus 5 minutes for the 76 mm 3-K cannon).
In addition, the 52-K served as the basis for the creation of the D-5 and ZIS-S-53 tank guns, which were subsequently installed on the SU-85 self-propelled guns and on the T-34-85, KV-85 and IS-1 tanks.
In general, for its time, which includes both design and industrial capabilities, the 52-K gun was quite good.
I will say more: it was not better for the period 1941-1944. In 1942, when the Germans had "tigers", the 52-K was the only weapon that could hit these tanks almost without problems.
A 76-mm cannon shell could penetrate the Tiger's side from 300 meters, and even then, with a 30% probability. The armor-piercing shell of the 85-mm cannon quite confidently hit the Tiger from a distance of 1 km into the frontal projection.
In 1944, a modernization was carried out, which improved the performance of the 52-K, but did not go into the series due to the fact that the urgent need had already disappeared.
In total, for the period from 1939 to 1945, the industry of the USSR produced 14,422 52-K guns.
After decommissioning, the gun was widely supplied abroad. And it sold pretty well.
And even in our time, 52-K is quite successfully used as an avalanche gun.
In our time, the strengths and weaknesses of the 85-mm Soviet and German 88-mm anti-aircraft gun have been repeatedly discussed. Indeed, "akht-komma-aht" has covered itself with glory and has earned a reputation as an excellent weapon. But the fact is that 52-K was in no way inferior to her. And in the same way she dropped German planes to the ground and stopped tanks.
It is not worth repeating, the fact is that the gun came out very decent, judging by the results.
